Steam plate



Aug. 11, 1925.

c. STEENSTRUP STEAM PLATE Filed Jan. 6, 1923 /7 Fig.2.. 2O 51 Fig 3.

Inventor:

V m 25 um SM n .B a

' Patented Aug. Il, 1925.

UNITED STATES CHRISTIAN STEENSTRUP, OF SCHENECTADY, NEW YORK, ASSIGNOR GENERAL TRIC COMPANY, A CORPQRATION OF NEW YORK.

PATENT OFFICE.

s'rmm rILATE.

Application filed January 6, 1923. Serial No. 611,198.

To all whom it may concern:

Be it known that I, CHRISTIAN STEEN- sTRUP, a citizen of the United States, residing at Schenectady, county of Schenectady,

State of New York, have invented certain new and useful Improvements in Steam Plates, of which the following is a specification.

The present invention relates to steam plates and more especially to those of large size which are used in hydraulic or other power presses to consolidate materials of various kinds to form sheets.

The requirements as to these plates when in service are very exacting, particularly when used in the manufacture of large sheets of insulating material, such as laminated mica and compositions of canvas and a binder, which have to be very exact as to thickness and have smooth surfaces. Further, the plates have to be provided with arrangements whereby they can be alternately heated and cooled. Heretofore the best plates have been made in two ways. One way is to make them of cast metal with heating and cooling passages cast therein. When made in. this manner each plate has to be relatively thick to obtain the necessary strength with the result that very few plates can be put into a press at one time and hence the output of the press for a given period of time is distinctly limited. Further, it is a. difficult matter to get satsifactory castings with perfectly smooth top and bottom sufaces and which are not porous at one or more points. The rejection for poor castings with this type is high.

The other way is more satisfactory in the final results but the plates are exceedingly expensive costing from $250 to $300 for arelatively thick and therefore take up a relatively large amount of space in the press.

My invention has for its object to improve the construction of steam plates of the character above referred to. Briefly, my improvements are directed to decreasing the cost of manufacture both in labor and material, and to making the plates thinner without impairing their rigidity so that a greater number can be used in a given press,thereby substantially increasing the output of the press for each operation.

For a consideration of what I believe to be novel, and my invention, attention is directed to the accompanying description and the claims appended thereto. In the accompanying drawing which is illustrative of my invention, Fig. 1 is a plan view of a steam plate with certain of the parts broken away; Fig. 2 is an edge view of the same, and Fig. 3 is a plan view of a steam plate for a coil mold with certain of the parts broken away.

Referring to the drawing, 4 and 5 indicate two rolled steel sheets which form the top and bottom members of the plate. These are finished as smooth as possible on their inner surfaces, preferably by grinding. Each sheet is provided with a large number of holes arranged in rows and located therein are spacing and supporting studs 6. Each stud has two ends of reduced section and an enlarged body portion 7 which serves to separate the sheets and also to transmit the pressure exerted on one of them to the other. The reduced ends of the studs are slightly longer than the sheets are thick so that they project slightly beyond the face and are upset slightly to temporarily hold the sheets together. In practice it is preferable to slightly round 05 the corners of the outer ends of the studs so as to facilitate the assembling operation, it being understood that all ELEC- of the studs are first inserted in one sheet after which the second sheet is mounted in place. The projecting ends, however, are removed in the final machine operation. In,

addition, these studs also form supports for the thin division strips or partitionsv 8 which tion. Some of these partitions, such as 9, for example, are made in two pieces with their outer ends in contact with the two side walls 10 of the plate and a space 11 between the adj accnt ends to form a passage for steam and cooling water. These partitions are perpendicular to the sheets and may be anchored to the side walls by welding or brazing. as indicated at 12 to prevent them from shifting in position during the manufacturing operations and also to prevent the formation of small passages formirg shunts to the main passage. Other partitions such as 13 for example. also extend perpendicular to the faces of the sheets and are held in position by frictional engagement with the studs. At opposite ends of each such partition, spaces 14 are provided which form passages for steam and cooling water.

The four sides or edges of the plate are formed of cold rolled steel bars 10 and 15 which may be square or rectangular in crosssection. The upper and lower surfaces are finished smooth so that they will make good joints with the sheets. These bars cooperate with the sheets to form a shallow chamber 16, and the latter is divided by the partitions 8 in such manner as to form a tortuous passage for the steam and water as indicated by the arrows. At the corners the bars are slotted, and located in the slots are small locking pieces of metal 17 which serve to hold the bars during the manufacturing operations and also help in rendering the joints tight. As the bars are situated between the sheets they serve to directly transmit pressure from one to the other, and there is no danger of ruptured joints.

I have found the use of the locking pieces 17 to be of substantial value in the manufacture of these plates. Without them there is the possibility. of the butt joints between adjacent bars opening during the preliminary handling, to such an extent that the fusing operation will not completely unite the parts and therefore the plate will leak when subjected to fluid pressure. Since the locking pieces are tightly fitted into their receiving slots and since they extend across the joint it follows that due to the fusing operation they will effectively seal the cham her atall four corners.

As above stated the studs temporarily hold the structure together, and the bars are so fitted as to be temporarily retained in place by friction.

An an additional precaution to prevent the bars from shifting during the preliminary handling, and prior to the fusingoperation, it is desirable to insert a few small rivets such as 18 along the outer edges of the plate. Another way to accomplish the same result is shown in Fig. 3. In this case the sheets and bars are united in a few spots such as 19 by electric welding.

The studs are shown as having shoulders at opposite ends which is the preferred construction. I or small plates these shoulders may be omitted and the union of the sheets and studs by fusion relied upon to transmit pressure from one sheet to the other.

After the parts are thus temporarily united they are permanently united by the fusion of metal. To do this the plate as a whole is placed in a hydrogen furnace together with a small amount of copper which is properly distributed over the same. The furnace is then heated to a point above the melting point of the copper when the latter will flow into all of thejoints between the parts and unite the same into a fluid-tight unitary whole. After the plate is cooled the bars are bored and tapped to receive the pipes 20 through which steam to heat the plate and water to cool it are admitted and exhausted. As shownthere are two admission pipes at the upper end and two discharge pipes at the lower end. The next step is to grind the upper and lower faces of the plate to remove any irregularities including the projecting ends of the studs and to ensure smooth working faces.

In Fig. 3 is shown a steam plate especially intended for use in molding coils for electrical apparatus. It is constructed in the same manner as above described but is smaller and is shaped to conform to that of the coil which is to. be pressed. Heretofore the best of these devices were made of bronze castings and were very expensive. On account of the difliculty in casting there were many rejections, due to porous spots, which of course increased the cost of manufacture. In this case only one partition is,

makes the plate as a whole much thinner.

As a-matter of fact by using plates of this character I can put about more into a given press than with the old constructions, thereby increasing its output to that extent for each operation. By making the sheets relatively thin and of uniform section the heating and cooling actions are more uniform and are also substantially quicker with the result of further increasing the output of the press. As such sheets are uniformly denseand free from imperfections the rejections due to this cause are eliminated. The spacing studs are made in automatic screw machlnes which reduces their cost to a minimum. The holes may be punched or drilled. Preferably both sheets are drilled at the same time so that errors due to lack of ali nment of corresponding holes in the two s eets are avoided. If it so happens that an error is made and one stud is slightly out of line, the partitions in the chamber being thin and more orless flexible, will compensate therefor. On the matter of cost, a plate of certain size constructed as herein described, can be made for about $40, as contrasted with about $250 to $300 for a plate (if the same size of the best prior construction.

' In accordance with the provisions of the patent statutes, I have described the prin ciple of operation of my invention, together with the apparatus which I now consider to represent the best embodiment thereof, but I desire to have it understood that the apparatus shown is only illustrative and that the invention may be carried out by other means.

\Vhat I claim as new and desire to secure by Letters Patent of the United-States, is,-

1. In a device of the character described, the combination of a pair of relatively thin metal sheets, means for uniting the sheets along their edges and cooperating therewith to form a chamber, a plurality of individual spacing devices located between the sheets which also sustain the pressure exerted thereon, partitions between the sheets which divide the chamber into fluid passages, and conduit means for admitting fluid to and carrying it away from said passages.

2. In a device of the character described, the combination of a pair of relatively thin metal sheets, means for uniting the sheets along their edges and holding the same in spaced relation to form a chamber, a plurality of spacing devices arranged in rows between said sheets, each of said devices having shoulders to sustain the pressure exerted on the sheets, thin metal partitions which extend crosswise of the sheets and between the spacing devices to divide thechamber into fluid passages, and conduit means for admitting fluid to and carrying it away from said passages,

. 3. In a device of the character described, the combination of a pair of relatively thin metal sheets, means located between the sheets at their edges which cooperate therewith to form a chamber, a plurality of spacers located between the sheets to sustain the pressure exerted thereon, said means and spacers being fused to the sheets, partitions between the sheets to form a tortuous fluid passage, and means for admitting fluid to and carrying it away from said passage.

4. In a device of the character described, the combination of. a pair of thin perforated metal sheets. metal bars located between the sheets at their edges to form a shallow chamber between them, a plurality of shouldered studs whose reduced ends enter the perfora tions in both sheets, said bars and studs being fused to the sheets, partitions which are located between the studs to divide the chamber into fluid passages, and means for admitting fluid to and carrying it away from said passages." 1

5. In a device of the character described, the combination of a pair of thin sheets hav mg perforations arranged in rows, metal bar's between the sheets which form the boundary walls of' a chamber between the sheets, a plurality of studs each of which is provided with an enlarged central body and two ends of reduced section, said-ends entering the perforations in the sheets, the bars and reduced ends of the studs being fused to the sheets, partitions whichextend crosswise of the chamber and are supported by the studs to divide the chamber into fluid passages, and means for admitting fluid to and carrying it away from said passages.

6. In a device of the character described,

the combination of a pair of thin perforated metal sheets, metal bars located in abutting end-to-end relation to each other between the sheets along the edges of the latter to form with said sheets a closed chamber, means for holding said bars in said abutting relation to each other and in said location between the sheets, spacing studs in the chamber extending between the sheets and having ends which enter the perforations in both sheets, said bars, sheets and studs havingengaging surfaces fused together to provide a unitary structure, and means within the chamber providing a tortuous fluid passage therethrough.

7 In a device of the character described, the combination ofa pair of thin perforated metal sheets, metal bars located in abutting end-to-end relation to each other between the sheets along the edges of the latter to form with said sheets a closed chamber, means for holding said bars in said abutting relation to each other and in said location between the sheets. spacing studs in the chamber extending between the sheets and having ends which enter the perforations in both" sheets, said bars, sheets and studs having engaging surfaces fused together to provide a unitary structure, and a plurality of spaced substantially parallel partitions extending between the plates and across the chamber, said partitions being alternately interrupted adjacent their ends and adjacent their centers to provide a tortuous fluid passage through the chamber. a

8. In a device of'the character described, the combination of a pair of thin perforated metal sheets, metal bars located in abutting end-to-end relation to each other between the sheets along the edges of the latter to form perforations in both sheets,

havingengaging surfaces fused together outlet conduits, said partitions being posithereby forming a unitary structure, fluid tioned between the spacing studs and held inletconduits connected with the chamber, by frictional en agement therewith, 10 fluid outlet conduits connected with the In Witness whereof, I have hereunto set 5 chamber, and a plurality of partitions withmy hand this 5th day of January, 1923.

in the chamber forming a tortuous fluid passage between said inlet conduits and said CHRISTIAN STEENSTRUP. 

